This invention relates to mounting of rotary abrasive tools onto drive spindles, especially by way of intervening mounting means adapted to secure the tool onto a threaded end of the spindle, for rotation about the axis of rotation of the spindle itself, even though the threaded end of the spindle may be somewhat misaligned.
Rotary abrasive tools, which function to shape other (usually rotary) tools or other devices, are necessarily shaped to very close tolerances so that the objects worked thereby are formed as desired. The alignment problem becomes even more critical, if possible, in rotary dressing tools whose function is to restore other abrasive tools to proper condition after some degree of wear.
Frequently a rotary dressing tool is secured to a supporting spindle by being threaded thereonto. Proper alignment between the supporting spindle and the supported dressing tool may be assured by
(1) abutment of a positioning face on the tool perpendicular to its axis of rotation against a similarly faced shoulder on the spindle,
(2) close fitting of a coaxial circumferential surface on the spindle into a coaxial bore in the dressing tool.
Regardless of how accurately the spindle and the rotary tool are shaped, and however precise the fit is between their respective positioning surfaces, the assembly may be misaligned if the axis of the threaded spindle end fails to be completely concentric with the axis of support of the tool by the spindle. A gross misalignment will prevent assembling the tool onto the spindle, but even a small discrepancy will tend to misalign the tool--if not by total axial offset, then by non-parallellism (tilt or cocking). Adjustable fastening nuts and similar retaining devices are known in a number of applications, but not as having compensated satisfactorily for the alignment problem just described.